An odds screen is a live table that shows the prices many bookmakers are offering on the same events, side by side, one column per bookmaker. You use it to see the best available price before you bet, to spot when one bookmaker is out of line with the rest of the market, and to watch prices move. The useful part is not just finding the highest number: it's reading the screen well enough to tell whether that number is actually a good price.
This guide walks through every part of a typical screen with a worked Australian example in decimal odds, including the two steps most guides skip: taking commission off exchange prices, and working out a fair price to compare against.
What an odds screen shows
Most screens, including the BetBank odds screen, share the same layout:
- Rows are the outcomes: each team in a head-to-head, each side of a line or total, or each runner in a race.
- Columns are bookmakers, usually with the highest price in each row highlighted.
- A best price column pulls the top price for each outcome into one place.
- A market percentage (also called the book, overround or margin) shows how much each bookmaker is charging on that market.
- A reference or fair price from a low-margin source, such as a betting exchange, gives you something to measure the other prices against.
- Movement indicators show whether a price has firmed (shortened) or drifted (lengthened) since it opened or since you last looked.
US sites often call this a "sportsbook odds screen" because Americans say sportsbook where Australians say bookmaker. It's the same tool.
How to read an odds screen: a worked example
Here's an illustrative AFL head-to-head with four bookmakers and an exchange. The prices are invented to show the method.
| Source | Team A | Team B | Market % |
|---|---|---|---|
| Bookmaker 1 | 1.80 | 2.00 | 105.6% |
| Bookmaker 2 | 1.85 | 1.95 | 105.3% |
| Bookmaker 3 | 1.78 | 2.05 | 105.0% |
| Bookmaker 4 | 1.83 | 1.98 | 105.2% |
| Exchange (back) | 1.87 | 2.12 | 100.6% |
Step 1: Read the market percentage
Each price implies a probability of 1 divided by the odds. Add them up across every outcome and you get the market percentage. The amount above 100% is the bookmaker's margin, its built-in expected profit on a balanced book, as Wikipedia's page on the mathematics of bookmaking explains.
For Bookmaker 1: 1/1.80 + 1/2.00 = 55.6% + 50.0% = 105.6%. So that bookmaker is charging about 5.6% on this market. Our guides to vig and implied probability go deeper on the conversion.
Step 2: Take the best price for each outcome
The best bookmaker price on Team A is 1.85 and on Team B is 2.05. If you could only bet with the highest number every time, your market would be 1/1.85 + 1/2.05 = 54.1% + 48.8% = 102.8%. Taking the best price on each side cuts the margin you're up against roughly in half. That's the whole case for line shopping, shown in one row.
What it's worth in dollars: a $50 bet on Team A that wins returns $92.50 at 1.85 and $89.00 at 1.78. That's $3.50 more on the same result, or about 9% more profit on that bet.
Step 3: Take commission off exchange prices
The exchange row looks like the best price on both sides, but those numbers are before commission. Betfair charges commission on net winnings at a Market Base Rate that, according to Betfair Australia, is 6% on most sports markets and 10% on NRL, with Australian racing mostly at 8%.
To compare fairly, convert the exchange price to an effective price:
Effective odds = 1 + (odds minus 1) × (1 minus commission rate)
At 6%, Team B's 2.12 becomes 1 + 1.12 × 0.94 = 2.05, the same as Bookmaker 3. Team A's 1.87 becomes 1.82, worse than Bookmaker 2's 1.85. A screen that shows raw exchange prices next to bookmaker prices without this adjustment flatters the exchange.
Step 4: Work out a fair price
The exchange market is close to 100%, which makes it a useful reference. Strip out its small margin by dividing each implied probability by the total (100.6%):
- Team A: 53.5% ÷ 1.006 = 53.1%, a fair price of about 1.88
- Team B: 47.2% ÷ 1.006 = 46.9%, a fair price of about 2.13
This is called de-vigging. More advanced screens blend several sharp references into a consensus fair price. A 2017 study by Kaunitz, Zhong and Kreiner used the average of many bookmakers' odds in a similar way to find mispriced football odds.
Step 5: Ask whether the best price is value
Expected value compares the price you can get with the fair price:
- Team A at 1.85 against a fair 53.1%: 0.531 × 1.85 = 0.983, an expected loss of about 1.7% per dollar staked.
- Team B at 2.05 against a fair 46.9%: 0.469 × 2.05 = 0.961, an expected loss of about 3.9%.
So in this example the best prices still carry a negative expected value. They just lose less than the alternatives. That's the most important lesson on any screen: highest is not the same as value. A bet is only positive EV when the bookmaker's price beats the fair price, and those spots are uncommon and usually short-lived. Our positive EV tool runs this comparison across the market for you, but the maths is the same as the five steps above.
Watching line movement
Prices on a screen are a snapshot. Watching how they change tells you more:
- A reference price moves and a bookmaker doesn't. If the exchange shortens Team A from 1.87 to 1.75 and one bookmaker is still showing 1.85, that bookmaker is now well above the new fair price. It may update within seconds, so check the timestamp.
- Every column moves together. Usually news: a late out, a weather change, a scratching. The market has adjusted, and the old prices are gone.
- One bookmaker moves alone. Often it's managing its own liability, not new information.
The price at the start of the event, the closing line, is the market's best estimate of the fair price. Comparing the price you took with the close is how you measure whether you're consistently getting good numbers. See our guide to closing line value.
Odds screens for racing
Racing screens work the same way with more rows. Add up 1 divided by each runner's price to get the market percentage. With many runners, the total usually sits well above a two-way sports market, so the gap between the best and worst price on a single runner can be large.
Three things to watch on racing screens:
- Fixed odds and tote are different products. A tote dividend isn't known until the pool closes, so it can't be compared like-for-like with a fixed price. The BetBank racing odds screen shows fixed odds only.
- Scratchings change everything. When a runner is scratched, other prices are adjusted and deductions may apply, so a screen captured before the scratching is out of date.
- Exchange commission is higher on racing. Use the right rate for the state and race type when you convert exchange prices.
Common mistakes when using an odds screen
- Trusting a stale price. If a price looks far out of line, check the update time and open the bookmaker's own page before you act.
- Comparing raw exchange prices. Take commission off first, as in Step 3.
- Treating the best price as a tip. A screen tells you where the best price is, not what will win. It's a pricing tool, not a reason to bet.
- Ignoring limits. Bookmakers can restrict accounts that regularly take their best prices. The Kaunitz study reports exactly that happening to the researchers once their betting was consistently successful.
- Including books you can't legally use. International screens may list offshore operators. Only bet with bookmakers licensed in Australia. GambleAware NSW warns that offshore sites can refuse self-exclusion, keep unspent balances or decline to pay large wins, with little recourse.
Using an odds screen well
A screen is most useful when you already know what you're looking for. Set it to the bookmakers you actually hold accounts with, check the market percentage before anything else, convert exchange prices, and compare against a fair price rather than the next-best bookmaker. Then record the price you took and the closing price so you can see over time whether your prices are any good.
If you want to try it on this weekend's AFL, NRL or racing markets, open the BetBank odds screen, filter to your bookmakers and run the five steps above on a market you're already watching.
18+ only. Betting involves risk and you can lose money: set a limit, never chase losses, and gamble responsibly. If you need a break, BetStop lets you block yourself from all licensed Australian online and phone betting for free.